JeffinMS wrote:

After changing the filter, I cut the old sponge as someone suggested and
pushed it down inside the new bio filter, Ill leave it for a few days. But I
noticed the fish are very very active now. At first I thought it might have
had something to do with going from a 20 gal filter to a 40 gal filter (160
gpm). I decided to test the water. Water clarity is increasing, after the
loss of the other filter I had some serious cloudiness. But these are
current readings.

Temp: 83 f.
Nitrate: 20 PPM
Nitrite: 0 PPM
Total Hardness: 425 PPM (Something wrong here)
Alkalinity/Buffering Capacity: 180-240 PPM
Ph: Between 7.2 and 7.6

The fish are swimming around like crazy. They used to slowly swim around the
tank, now its all over and very fast. What do I need to do to correct any of
the above?

I think your fish are trying to escape. You don't say what your ammonia
reading is. This is the first test you should do, asap. By the time
nitrite registers anything all your fish could be dead. If your filter
stopped for many hours then the tank will go through another cycling. If
the tank is heavily stock then that may not happen without many
casualties. You need to get some used filter media from someone you know
that has a tank, or from your LFS. Cloudiness is a bad sign, and also
related to damage of your biological filter. Your pH reading doesn't
look right. I'd expect a pH of at least 8.1 at the GH and KH given.

Nikki